Kill Switch or Ignition Switch ?
Road Captain
Joined: May 2009
Posts: 642
Likes: 0
From: Haslet, Texas
An interesting question. Procedurally we could be right either way, but as an aviator I can see the sequential method of Kill then Ignition being more than just a technique. Thinking of the Ignition as the power supply and the Run/Kill as the logic switch enabling an engine start sequence.
While the Ignition will "kill" the engine run cycle, there is a reason for two switches in the circuit. Let's say you disregard the Run/Kill and always use the Ignition switch. The starter switch is dependent on power from the Run/Kill switch to engage the starter. Let's assume there is a malfunction in the starter relay and you switch the Ignition to IGN. With the Run/Kill in the Run position your bike (assuming it's not equiped with a clutch starter cutout switch) will be off the stand and on its side before you can reach the Ignition switch.
Like I said, it's a possible reason for the two switches, but he Run/Kill will control when you want to engage the starter and not the other way around. Cars have a Run/Kill switch. It's the function of placing pressure on the brke pedal enabling the key or Start/Stop button (in newer vehicles) to engage the starter motor. Even our 08 BMW with automatic trans requires this action to start. Think of the Run/Kill as the way to signal your intent and preparedness to start your bike.
Just my two cents. In planes and helicopter we have start sequences with speed switches and other procedural requirement that could easily be eliminated with the ability to just turn on the power and crank the engine, but these procedures allow sequencing of specific systems to allow safe starting and shutdown of engines.
While the Ignition will "kill" the engine run cycle, there is a reason for two switches in the circuit. Let's say you disregard the Run/Kill and always use the Ignition switch. The starter switch is dependent on power from the Run/Kill switch to engage the starter. Let's assume there is a malfunction in the starter relay and you switch the Ignition to IGN. With the Run/Kill in the Run position your bike (assuming it's not equiped with a clutch starter cutout switch) will be off the stand and on its side before you can reach the Ignition switch.
Like I said, it's a possible reason for the two switches, but he Run/Kill will control when you want to engage the starter and not the other way around. Cars have a Run/Kill switch. It's the function of placing pressure on the brke pedal enabling the key or Start/Stop button (in newer vehicles) to engage the starter motor. Even our 08 BMW with automatic trans requires this action to start. Think of the Run/Kill as the way to signal your intent and preparedness to start your bike.
Just my two cents. In planes and helicopter we have start sequences with speed switches and other procedural requirement that could easily be eliminated with the ability to just turn on the power and crank the engine, but these procedures allow sequencing of specific systems to allow safe starting and shutdown of engines.
Outstanding HDF Member
Joined: Dec 2007
Posts: 2,803
Likes: 11
From: El Paso, Texas
An interesting question. Procedurally we could be right either way, but as an aviator I can see the sequential method of Kill then Ignition being more than just a technique. Thinking of the Ignition as the power supply and the Run/Kill as the logic switch enabling an engine start sequence.
While the Ignition will "kill" the engine run cycle, there is a reason for two switches in the circuit. Let's say you disregard the Run/Kill and always use the Ignition switch. The starter switch is dependent on power from the Run/Kill switch to engage the starter. Let's assume there is a malfunction in the starter relay and you switch the Ignition to IGN. With the Run/Kill in the Run position your bike (assuming it's not equiped with a clutch starter cutout switch) will be off the stand and on its side before you can reach the Ignition switch.
Like I said, it's a possible reason for the two switches, but he Run/Kill will control when you want to engage the starter and not the other way around. Cars have a Run/Kill switch. It's the function of placing pressure on the brke pedal enabling the key or Start/Stop button (in newer vehicles) to engage the starter motor. Even our 08 BMW with automatic trans requires this action to start. Think of the Run/Kill as the way to signal your intent and preparedness to start your bike.
Just my two cents. In planes and helicopter we have start sequences with speed switches and other procedural requirement that could easily be eliminated with the ability to just turn on the power and crank the engine, but these procedures allow sequencing of specific systems to allow safe starting and shutdown of engines.
While the Ignition will "kill" the engine run cycle, there is a reason for two switches in the circuit. Let's say you disregard the Run/Kill and always use the Ignition switch. The starter switch is dependent on power from the Run/Kill switch to engage the starter. Let's assume there is a malfunction in the starter relay and you switch the Ignition to IGN. With the Run/Kill in the Run position your bike (assuming it's not equiped with a clutch starter cutout switch) will be off the stand and on its side before you can reach the Ignition switch.
Like I said, it's a possible reason for the two switches, but he Run/Kill will control when you want to engage the starter and not the other way around. Cars have a Run/Kill switch. It's the function of placing pressure on the brke pedal enabling the key or Start/Stop button (in newer vehicles) to engage the starter motor. Even our 08 BMW with automatic trans requires this action to start. Think of the Run/Kill as the way to signal your intent and preparedness to start your bike.
Just my two cents. In planes and helicopter we have start sequences with speed switches and other procedural requirement that could easily be eliminated with the ability to just turn on the power and crank the engine, but these procedures allow sequencing of specific systems to allow safe starting and shutdown of engines.
Tourer
Joined: May 2010
Posts: 312
Likes: 4
I was told by the dealer who sold me my (used) bike that I should use the kill switch so if I turn the ignition switch to for music, light, etc, the fuel pump won't be powered and pressurize the system.
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Road Warrior
Joined: Mar 2007
Posts: 1,383
Likes: 3
From: Texas City, TX
Whatever you do - do NOT ArmorAll your tires. No matter who in here tells you to.
Try it anyway, you'll see!
Ride Safe, (especially if you decide to ArmorAll your tires!)
Steve R.
Cruiser
Joined: Sep 2007
Posts: 205
Likes: 0
The reason you should use the kill switch is that when you already have the kill switch on when you turn on the main switch, you could overload the system and blow a fuse. If you turn on the main switch and let it powerup head lamp and fuel pump, then turn on kill or secondary switch, it is better for the elctrical system. I never turn on and off with main switch. I get frustrated at dealership watching the wrenches do it tho. Just do what you want...Bldr
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